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Objective To research the effect of cavity under Bolus to anisotropic analytical algorithm (AAA) on calculation precision of dose in shallow tissue based on Monte Carlo method;Methods A 30 cm × 30 cm × 30 cm water phantom with the upper surface was constructed which was located at the source-axis distance (SAD) of the medical linear accelerator and the center as well as coincided with the central axis of the radiation field in Eclipse treatment panning system. Above the water phantom, a water film of 1 cm thick with or without different cavities was constructed or. AAA was used to calculate the dose distribution on the central axis and the x-axis of different depth of the water model with different cavities respectively. The accelerator model, the same water phantom and the water film were constructed and the dose distributions of the same positions were calculated with Geant4. Based on the Geant4 calculation result, the calculation precision of AAA with different cavity were compared;Results For cavities with area of 2 cm × 2 cm, if the thickness is smaller than 0.5 cm, the AAA calculation error is about 2%. with the cavity thickness increase, the AAA would overestimate the dose in the shallow area under the cavity. With the cavity area increase, the area where AAA overestimate the shallow dose gradually moved out until near the edge of the radiation field, and the calculation error on the central area gradually reduced until there is basically no error. Conclusions The shallow dose would be increased according to the cavity size when planning with AAA; If there are cavities with large volume, it is better to reposition.
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Objective:To analyze the correlation between the Naples prognostic score (NPS) after preoperative neoadjuvant chemoradiotherapy in locally advanced rectal cancer (LARC) and evaluate the prognostic value of NPS in LARC.Methods:136 patients with LARC meeting the recruitment criteria from 2015 to 2020 were selected. Serum albumin, total cholesterol (TC) were collected and neutrophil-lymphocyte ratio and lymphocyte-monocyte ratio were calculated. All patients were scored and graded according to the NPS rule. The survival rate was calculated with Kaplan- Meier method. Multivariate prognostic analysis was performed by Cox models. Results:There was no significant correlation between NPS score and tumor regression or pathological complete response (pCR) of LARC patients after neoadjuvant therapy ( P=0.192, P=0.163). However, Cox multivariate analysis showed that NPS was an independent risk factor for overall survival (OS) and disease-free survival (DFS) of LARC ( P=0.009, P=0.003), and hierarchical analysis suggested that LARC patients with lower NPS score obtained better prognosis. Besides NPS, tumor size was also an independent risk factor for OS, and tumor size and N stage were the independent risk factors for DFS. Conclusion:NPS has no correlation with tumor regression or pCR for LARC after neoadjuvant chemoradiotherapy, whereas it could serve as an effective predictor for long-term prognosis of LARC.
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Objective To compare the efficacy and safety of two concurrent chemoradiotherapy regimens between paclitaxel plus fluorouracil( TF) and cisplatin plus fluorouracil ( PF) in the treatment of locally advanced esophageal squamous carcinoma. Methods 103 patients with locally advanced esophagus carcinoma were treated in Affiliated Hospital of Jiangnan University from December 2014 to February 2016, and randomly assigned to either study group ( TF ) or control group ( PF ) according to random number table, of which 52 patients in the TF group while 51 patients in the PF group. The primary outcome was overall survival(OS), and secondary outcomes include progression-free survival(PFS), local progression-free survival( LPFS) and side effects. Results The 1-year OS for TF group was 76. 9％ versus 74. 5％ for PF group( P>0. 05 ) , and the 2-year OS for TF group was 59. 6％ versus 56. 9％ for PF group ( P >0. 05). The 1-year LPFS for TF group and PF group were 71. 2％ and 66. 7％ respectively(P>0. 05), and the 2-year LPFS for TF group and PF group were 61. 5％ and 58. 8％ respectively(P>0. 05). The 1-year PFS for TF group was 63. 5％ versus 62. 7％ for PF group ( P>0. 05 ) , and the 2-year PFS for TF group was 51. 9％ versus 39. 2％ for PF group ( P>0. 05 ) . The incidence rate of serious ( grade 3- 4 ) leukopenia for TF group was 36. 5％ versus 17. 6％ for PF group(χ2 =4. 642, P<0. 05). The incidence rate of serious (grade 3-4) acute radiation pneumonitis was 15. 4％ in the TF group, higher than that in the PF group with the rate of 3. 9％(χ2 =3. 859, P<0. 05), while the incidence rate of severe nausea and vomiting for PF group was 17. 6％ versus 1. 9％ for TF group(χ2 =7. 262, P <0. 05). The difference between the two groups was statistically significant. Conclusions Patients who were treated with two concurrent chemoradiotherapy regimens showed no difference in OS, PFS and LPFS. The regimen on the basis of Paclitaxel has higher risk of adverse effects incidence rates of hematological toxicity and acute radiation pneumonitis, while digestive system toxicity must be concerned when concurrent chemoradiotherapy is performed on the basis of cisplatin plus fluorouracil.
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Objective To evaluate intra-operative radiotherapy after breast conservative surgery in early breast cancer patients in terms of postoperative complications,cosmetic outcome and recurrence events.Methods From June 2007 to Dec 2010,115 early breast cancer patients received breast conserving surgery.Fifty-nine patients (study group) received intra-operative radiotherapy,compared with 56 patients (control group) receiving routine postoperative radiotherapy.Postoperative complications were evaluated 1 month after surgery; cosmetic outcome was evaluated 1 year postoperatively; recurrence and death events were followed up.Results The average wound healing time was 13 -22 days in study group and 9 - 14days in control group.In the study group,2 patients developed fat deliquescence,16 patients showed wound edema while no such side effects were found in control group.No infection or hematoma were found in either group.Overall cosmetic outcome was rated 1 year post operation.In the study group (41 cases),36 patients were graded as excellent or good,5 patients were as fair or poor.Meanwhile in the control group (37 cases),wounds in 25 patients were graded as excellent or good,that in 12 patients were as fair or poor (P =0.031).After a follow-up from 3 to 42 months(median:24 months),two patients (3.39％) in study group developed local cancer relapses,one of them( 1.7％ ) died.In control group,one patient ( 1.8％ )developed local relapse,and no one died.Conclusions Intra-operative radiotherapy is safe and reliable with good cosmetic outcome.
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Objective To observe the effect of residual tumor after radiotherapy on survival rate of patients with nasopharyngeal carcinoma (NPC). Methods From Jan. 1989 to Dec. 1998, 108 of 304 NPC patients pathologically confirmed, had residual tumor after radical radiotherapy, of whom, 26, 68, 14 had residual lesion in the nasopharyngeal cavity alone, cervical lymph node alone, and nasopharyngeal cavity plus cervical lymph node. Results The overall 1 , 3 , 5 , and 10 year survival rates (OS) significantly decreased in the residual group. The highest OS was in the group with nasopharynx residual alone, and the lowest in nasopharynx plus residual lymph node group. The bigger the residual lesion, the lower the OS. Conclusions The overall survival rate decreases in patients with residual lesion after radiotherapy, especially in patients with both nasophrynx and regional lymph node residual. Tumor residual after radiotherapy can be a prognostic indicator for patients with NPC.